Alps keyboard codes

Alps keyboard codes typically contain a segment of the part number of the switch, which provides clues to help identify the part numbers of the switches themselves.

Code structure

Alps keyboards are marked with either one or two defining codes. The PCB code is written into the PCB in un-etched copper and typically begins "12K" (older keyboards) or "56AAA" or "57AAA" (newer keyboards); membrane keyboards may have this code written on the membranes instead. The format of these codes is not understood, but it provides the third letter in the switch series. For example, 12KC538A denotes SKCC, SKCL or SKCM switches.

The completed assembly may also be affixed with an assembly label; this can be found on either the plate or the PCB. These labels have typically two codes, of which one is never understood. The other type of code begins "K" or "KF" and it provides letters three and four of the switch series. For example, KFFLEB004C indicates Alps SKFL series. In the case of KFFBA010, this is taken to be SKFF series on the assumption that there is no extraneous "F": KFFBA010.

The importance of these codes is clear: obtaining these codes provides the identity of Alps switch series in the absence of any catalogues or datasheets. Alps SKFL series was identified solely using the KFFLEB004C code, which was subsequently confirmed true by search engine results for a stock of surplus SKFL series switches sold by Technology Transplant. The KF codes—that identify the full series name—are comparatively rare; the best source of these is Canon typewriters, which were consistently provided with these labels and which used a wide variety of Alps switch types.

Known codes

A circle is assumed to be "0" (zero) not "O". Years given are for the reference keyboard cited.